Cooks had the fastest clocking among the wide receivers, at 4.33 seconds. Mayock said Cooks "is one of my favorite players," has "fantastic hands" and that he should go late in the first round or early in the second. "This kid's special with the ball in his hands," Mayock said.

Texas A&M's Mike Evans, who is 6-foot-5 and 231 pounds, had a 4.53 clocking. Mayock says he is "a top-15 pick in today's NFL" and compared him to Tampa Bay's Vincent Jackson. Mayock says Evans must become a better route runner. "He is going to have to learn how to create separation with his body," Mayock said.

Division II Pittsburg State's John Brown was the second-fastest receiver, clocking 4.34. Mayock said Brown, a Miami native who attended three schools, was impressive at the East-West Shrine Game and has potential as a return man. Mayock said Brown has both quickness and speed and "can get in and out of his breaks efficiently."

Ole Miss' Donte Moncrief and Colorado's Paul Richardson tied for the third-fastest time, at 4.40. Moncrief's time was especially impressive, considering he is a 225-pounder.

Clemson's Martavis Bryant, who is 6-4, ran a 4.42, and at his size, Mayock noted, "That's awesome." He was tied with 212-pounder Jeff Janis of Division II Saginaw Valley State for the fifth-fastest time.

Florida State's Kelvin Benjamin, who is 6-5, 240 pounds, clocked a 4.61, impressive for a player his size. But Mayock said a fast 40 time wasn't really all that necessary for a guy such as Benjamin because of his size.

LSU's Odell Beckham Jr. ran a 4.43. NFL Network analyst Michael Irvin said he had talked with Beckham before the workout and that Beckham was upset that the NFL had banned players from wearing a certain kind of shoe. Obviously, in the end, it didn't bother Beckham all that much.

Vanderbilt's Jordan Matthews is the leading receiver in SEC history, and some scouts questioned his straight-ahead speed. But he turned in a faster-than-expected 4.46 clocking, which should ease some of the concerns about his speed..

Mike Huguenin can be reached at mike.huguenin@nfl.com. You also can follow him on Twitter @MikeHuguenin.